- Contingency tables. Using two categorical variables with two to five levels each, specify a hypothesis test for homogeneity of proportions associated with your research questions.
- (2 p) Specify the hypotheses in words and notation.
- (2 p) State the conclusion of the test in the context of the problem.
- (1 p) Check the assumptions of the test.
- (1 p) Indicate which cells have Pearson residuals more extreme than \(\pm 2\).
- (2 p) Plot a mosaic plot of the data and Pearson residuals.
- (2 p) Interpret the mosaic plot with reference to the Pearson residuals.

Turn in your master HW file with these sections appended to the bottom.

Class 21: Parts 1-3 from above with points for each part: 4, 4, 2.

Class 22: All parts from above, with a focus on the last two.

The sections from Erikโs `S4R_Project_All_Erik_NESARC.Rmd`

file to focus on are

- Class 21 Contingency tables